Thermic telltale



April 21, 1942' H. L. HEXAMER 2,280,755

' THERMIC TELLTALE Filed Oct. 28, 1959 I PatentediApr. 2l, 1942 l THEBMIC TELLTALE Homer L. Hexamer, Canton, Ohio, assigner to The Timken Roller Bearin Ohio, a corporation of g Company, Canton7 Ohio Application October 28, 1939, Serial No. 30L7l5 3 Claims. (Cl. 116-166) 'Ihis invention relates 'to thermic telltales for indicating an' overheated condition in various constructions. The invention has for its principal object to provide a simple and eillcient signaling device of inexpensive and compact con-v f struction which can be readily incorporated in various constructions, as for example, a bearing construction, and which is adapted to operate at a predetermined temperature to indicate to the sense of sight, smell, or both, an excessive temperature in the construction in which it is incorporated. The invention consists in the thermic telltale and in the construction, combinations, and arrangements hereinafter described and claimed. In the accompanying drawing, which forms part of this specification and wherein like symbols refer to like part-s wherever they occur,

Fig. l is a vertical longitudinal section through the end portion of a roller bearing axle construction provided with a thermic telltale embodying my invention, n

Fig. 2 is an enlarged central longitudinal section through said telltale,

Fig. 3 is a transverse section on line 3 3 in Fig. 2,

Fig. 4 is a vertical longitudinal section through said telltale in the region of the fusible seal therefor,

Fig. 5 is an enlarged 'central longitudinal section through a modified form of telltale,

Fig. 6 is a central longitudinal sectional view of another modied form of telltale,

Fig. 'l is an enlarged fragmentary section, slmilar to' Fig. 6, through the end closure member cf the telltale; and

Fig. 8 is a vertical longitudinal section of another rollerbearing construction provided with the telltale device shown in Figs. 6 and 7. Referring to Fig. 1 of the accompanying drawing, my invention is shown in connection with a rollerl bearing axle construction; but it is also applicable to other antifriction bearing axle orA shaft constructions and to various other constructions where it is desirable to protect the construction against excessive temperatures.-

The construction shown comprises an axle I having a wheel 2 fixed to one end thereof, a lubricant containing housing 3 surrounding the axle inwardly oi said wheel and having a threaded drain opening 4 in its bottom, a roller bearing 5 interposed between the axle I and housing 3, and an end closure member 6 secured to the end of the housing for closing the annular space between the axle and housing. The roller bearing 5 comprises a series of conical rollers l interposed between a cone or inner raceway member 6 mounted on the axle l and a cup or outer race-1 way member@ mounted in the bearing housing 3.v

The above construction is' provided with a thermic telltale lli for: indicating to the sense of smell, sight, or both, an overheated condition in the roller bearing. The telltale is preferably embodied in said construction by being threaded into the drain opening 4 ofthe housing 3 to thereby constitute a plug for said opening. As mounted, the telltale. extends upwardly into the lubricant Il in the bearing housing.

As illustrated in Figs. 2 and 3, the telltale III comprises a hollow tubular portion or cartridge I2 having a plug member I3 secured to'its lower end in any suitable manner or if desirable integral therewith. On the upper portion of said plug member is an external thread I4 adapted to engage the Ithreaded drain opening 4 in the bottom of the axle housing. The lower outer portion Ib of said plug member is flat-sided and adapted to receive a wrench.

A central passageway or bore I6 leads through said plug member into a chamber I'I in the. hollow tubular portion I2 of the telltale device. The upper portion I8 oi this narrow passageway or bore l adjacent to the chamber is of smaller diameter than the lower portion and forms a seatadapted to seat a seal I9. 'I'he chamber in the hollow-tubular portion I2 of the telltale is adapted to contain an odoriferous or smoke producing liquid or both. 'Ihe seal I9 is in position to close the narrow upper end portion I8 of passageway or bore It of the plug and thus cut olf communication between the chamber Il and the portion of said passageway located outwardly of said seal.

`The seal comprises a cylindrical steel shell 2l with inturned end flanges II forming openings 22 at the ends of said shell. The steel shell contains a core 23 of fusible metal which closes the openings in the shell. This seal is pressiltted into the narrow upper portion I8 of the passageway I6 in the plug i3.

The plug member of the telltale is provided near its outer end with radial bores or passageways 2l adapted to receive a wire 25 which has one end anchored in a lug 26 provided therefor on the axle housing and has its other end twisted around the wire extending between said telltale device and said lug. This Wire prevents the telltale device from working loose in the opening.

The operation of my device is'as follows, the

chamber Il in -the hollow tubular portion of the 'telltale `device is, fined with' signaling material A and thus opens the passageway through the plug member, thereby establishing communication betweenthe chamber containing the signaling uid and the atmosphere. The escape of the signal fluid will constitute a warning which communicates to the sensev of sight, smell, or both, thereby indicating that the bearing requires attention.

The modification shown in Fig. 5 is similar 'to the preferred embodiment of my invention described above, the main difference being in the passageway or bore through the plug member and in the position of the seal. The passageway or bore 21 has the same diameter throughout in the modification and the seal 28 is pressfitted into the lower end thereof. The modification shown in this flgure does-not have a radial bore 24 through the plug member 29. Such a bore through the passageway 21 would permit the escape of the signaling material. This telltale is positioned in the axle housing the same as the telltale described above and it is similar in operation.

In Fig. 8, a modified telltale device is shown with a roller bearing journal box construction. The construction shown comprises an axle 30 having a whee1.3|` fixed at one end thereof, a housing 32 surrounding the axle, and an end closure plate 33. A roller bearing 34 is interposed between said housing and said axle. As shown in Figs. 6 rand '1, the telltale device 35 comprises a cylindrical container 36 having an end member 31 with a circular opening 38 in its central portion. The end member 31 is flanged inwardly around the opening, the flanges 39 providing a. support for a seal 40 which is pressfitted in said opening and has an enlarged head portion' 4| at'its outer end that seats against said end member. The telltale device 35 is mounted in a longitudinal bore 42 in the end closure plate 33 and abuts against the cup or outer raceway member 43 of the bearing 34. When the bearing becomes excessively hot, the

heat is transmitted to the other end of the telltale device to the seal and the fusible c`ore 44 in said seal melts permitting the signaling material toescape. y Y

The hereinbefore described telltale device has numerous advantages. It may be easily incorporated into many existing constructions without material alterations, it is practical and efflcient and may be removed and relled easily.

'Reference is hereby made to my copending application Serial No. 411,795, filed September 22, 1941, for subject .matter Ishown but not claimed herein.

What I claim is:

1. A thermic telltale comprising a sheet metal cup adapted to contain a signaling material, a sheet metal cover for said cup permanently united to the open endthereof to provide a leakproof closure therefor, said cover having a flanged opening extending therethrough in communication with the interior of said cup. and a fusible seal fitting within and closing said flanged opening in said cover. l

2.A thermic telltale comprising a sheet metal cup adapted to contain a signaling material, a sheet metal cover for said cup permanently united to the open end thereof to provide a leakproof closure thereof, said cover having an inwardly flanged opening extending therethrough in communication with the interior of said cup,

and a fusible seal fitting within and closing said anged opening in said cover, said seal comprising a tube pressfitted in said flanged opening in said cover and a fusible core in said tube.

3.A thermic telltalecomprising a sheet metal cup adapted to contain a signaling material, a sheet metal cover for said cup permanently 4 united to the open end thereof to provide a leakproof closure therefor, said cover having an inwardly flanged opening extending therethrough in communication with the interior of said cup,

and a fusible seal fitting with and closing said anged opening in said cover, said seal comprising a tube presstted in said flanged opening in said cover and a fusible core in said tube, said tube terminating at its outer end in an enlarged head portion adapted to seat against said cover around the outer end of the flanged opening therein and said cover having a hollow outstanding rib in'the outer face thereof surrounding said enlarged head portion of said tube.

HOMER L. HEXAMER. 

